Sir George Martin, the legendary music producer colloquially known as the Fifth Beatle for his collaborations with the seminal rock group, has died. Though the cause of death has not been disclosed, a representative from Martin’s management company has confirmed that he passed peacefully at his home in England. He was 90 years old.

An autodidact piano maven from a young age, music always defined Martin’s life and passions. After a brief stint in the military and an education at Guildhall School of Music and Drama, Martin found work at age twenty-four as the assistant to Oscar Preuss, the head of Parlophone Records. He’d take the small classical-music label over in 1955, establishing himself in the industry and paving the way for his eventual meeting of the minds with four lads from Liverpool in 1962. Though Martin would never enjoy the fame the befell John, Paul, George, and Ringo, he was a key component of the band and an essential architect of their constantly evolving sound. Martin’s nitty-gritty knowledge of theory and the careful mechanics governing music picked up whatever slack was left by the evident yet unrefined talent of the Beatles. The baroque curlicues that elevated their catalogue from pop excellence to next-dimension breakthrough mostly came from Martin: the string quartet on “Yesterday,” the piccolo trumpet solo on “Penny Lane,” the violins and violas on “Eleanor Rigby,” all Martin’s.

But beyond his most noted work with the Fab Four, Martin met with plenty of success. He produced novelty comedy records with Peter Sellers, Shirley Bassey’s immortal theme for Goldfinger, and assorted assistance for the likes of Jeff Beck, Celine Dion, and the band America. In 1996, he was Knighted by the Queen, the loftiest stature to which any Brit can aspire. By anyone’s measure, Martin lived an extraordinary life and left an indelible imprint on the face of music. It’s the great tragedy of being an expert producer that when your work is done properly, it’s absolutely invisible; thousands of working musicians today owe their whole careers to him, and don’t even know it.

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